/*
 * SPDX-FileCopyrightText: 2025 William Bell
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 */

#include "hashmap.h"

#include "../../../memory.h"
#include <gc.h>
#include <inttypes.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

struct hashmap_GC *createHashmap_GC() {
  struct hashmap_GC *t =
      (struct hashmap_GC *)ar_alloc(sizeof(struct hashmap_GC));
  t->size = 0;
  t->order = 1;
  t->list = NULL;
  t->hashmap_count = 0;
  t->count = 0;
  t->inline_count = 0;
  return t;
}

static int compare_node_asc(const void *a, const void *b) {
  const struct node_GC *na = *(const struct node_GC **)a;
  const struct node_GC *nb = *(const struct node_GC **)b;

  // Ascending order (smallest order first)
  if (na->order < nb->order)
    return -1;
  if (na->order > nb->order)
    return 1;
  return 0;
}

struct node_GC ** hashmap_GC_to_array(struct hashmap_GC *t,
                         size_t *array_length) {
  size_t array_size = 8;
  *array_length = 0;
  struct node_GC ** array = ar_alloc(array_size * sizeof(struct node_GC*));

  for (size_t i = 0; i < t->inline_count; i++) {
    if (*array_length >= array_size) {
      array_size *= 2;
      array = ar_realloc(array, array_size * sizeof(struct node_GC*));
    }
    array[(*array_length)++] = &t->inline_values[i];
  }

  for (size_t i = 0; i < t->size; i++) {
    struct node_GC *list = t->list[i];
    struct node_GC *temp = list;
    while (temp) {
      if (*array_length >= array_size) {
        array_size *= 2;
        array = ar_realloc(array, array_size * sizeof(struct node_GC*));
      }
      array[(*array_length)++] = temp;
      temp = temp->next;
    }
  }

  qsort(array, *array_length, sizeof(struct node_GC*), compare_node_asc);
  return array;
}

void clear_hashmap_GC(struct hashmap_GC *t) {
  if (!t->count)
    return;
  t->order = 1;
  t->count = 0;
  t->inline_count = 0;
  t->hashmap_count = 0;
  memset(t->list, 0, sizeof(struct node_GC *) * t->size);
}

void resize_hashmap_GC(struct hashmap_GC *t) {
  int old_size = t->size;
  int new_size = old_size * 2;
  if (new_size == 0)
    new_size = 8;

  struct node_GC **old_list = t->list;

  // Create new list
  t->list = (struct node_GC **)ar_alloc(sizeof(struct node_GC *) * new_size);
  memset(t->list, 0, sizeof(struct node_GC *) * new_size);

  t->size = new_size;
  if (!old_list)
    return;
  t->hashmap_count = 0;
  // Rehash old entries into new list
  for (int i = 0; i < old_size; i++) {
    struct node_GC *temp = old_list[i];
    while (temp) {
      hashmap_insert_GC(t, temp->hash, temp->key, temp->val,
                        temp->order); // Will increment count
      temp = temp->next;
    }
  }
}

int hashCode_GC(struct hashmap_GC *t, uint64_t hash) {
  return hash & (t->size - 1);
}

int hashmap_remove_GC(struct hashmap_GC *t, uint64_t hash) {
  for (size_t i = 0; i < t->inline_count; i++) {
    if (t->inline_values[i].hash == hash) {
      size_t length = t->inline_count - i;
      if (length > 1) {
        memmove(&t->inline_values[i], &t->inline_values[i + 1],
                (length - 1) * sizeof(struct node_GC));
      }
      t->inline_count--;
      return 1;
    }
  }
  int pos = hashCode_GC(t, hash);
  struct node_GC *list = t->list[pos];
  struct node_GC *temp = list;
  struct node_GC *prev = NULL;
  while (temp) {
    if (temp->hash == hash) {
      if (prev)
        prev->next = temp->next;
      else
        t->list[pos] = temp->next;
      return 1;
    }
    prev = temp;
    temp = temp->next;
  }
  return 0;
}

void hashmap_insert_GC(struct hashmap_GC *t, uint64_t hash, void *key,
                       void *val, size_t order) {
  if (!order) {
    order = t->order++;
  }
  for (size_t i = 0; i < t->inline_count; i++) {
    if (t->inline_values[i].hash == hash) {
      t->inline_values[i].val = val;
      return;
    }
  }
  if (!t->list && t->inline_count < INLINE_HASHMAP_ARRAY_SIZE) {
    t->inline_values[t->inline_count].hash = hash;
    t->inline_values[t->inline_count].key = key;
    t->inline_values[t->inline_count].val = val;
    t->inline_values[t->inline_count].order = order;
    t->inline_count++;
    t->count++;
    return;
  }
  if ((t->hashmap_count + 1) > t->size * 0.75) {
    resize_hashmap_GC(t);
  }

  int pos = hashCode_GC(t, hash);
  struct node_GC *list = t->list[pos];
  struct node_GC *temp = list;

  // Check if key exists → overwrite
  while (temp) {
    if (temp->hash == hash) {
      temp->val = val;
      return;
    }
    temp = temp->next;
  }

  // Insert new node
  struct node_GC *newNode = (struct node_GC *)ar_alloc(sizeof(struct node_GC));
  newNode->hash = hash;
  newNode->key = key;
  newNode->val = val;
  newNode->order = order;
  newNode->next = list;
  t->list[pos] = newNode;
  t->hashmap_count++;
  t->count++;
}

void *hashmap_lookup_GC(struct hashmap_GC *t, uint64_t hash) {
  size_t stop = t->inline_count;
  for (size_t i = 0; i < stop; i++) {
    if (t->inline_values[i].hash == hash)
      return t->inline_values[i].val;
  }
  if (!t->list)
    return NULL;
  int pos = hashCode_GC(t, hash);
  struct node_GC *list = t->list[pos];
  struct node_GC *temp = list;
  while (temp) {
    if (temp->hash == hash) {
      return temp->val;
    }
    temp = temp->next;
  }
  return NULL;
}